* 因为经常在console下面工作，操作文件的命令都还可以，但是想想用程式来操作，那也是更有意思，特别是在shell程序的时候…
* 熟悉*inx命令的人，相信对这些ruby的方法会很熟悉的
1. 操作目录（Directories）
A. 创建
Dir.chdir( “/Users/weston” ) #进入目录
home =Dir.pwd # => “/Users/weston/” * 显示目录
Dir.mkdir( “/Users/weston/” ) ＃创建目录，和*nix命令一样吧
Dir.rmdir( “/Users/weston/test” ) # 删除目录
Dir.mkdir( “/Users/weston/test”,755 ) #常见目录，设置权限
B.查看
d = Dir.entries( “/Users/weston” ).each { |e| puts e } #=> Array
＃ 当然会有些隐藏文件，很方便的用数组操作，不显示隐藏文件
d2 = d.delete_if{ |e| e=~ /^\..*/} #=>这样出来的就是不包含隐藏文件了
C. 打开目录
dir = Dir.open( “/Users/weston” ) # => #<Dir:0x1cd784>
dir.path # => “/Users/weston”
dir.tell # => “.”
dir.read # => 1
dir.tell # => “..”
dir.rewind # => rewind to beginning
dir.each { |e| puts e } # puts each entry in dir
dir.close # => close stream
2. 文件（ Files ）
A. 创建
file = File.new( “file.rb”, “w” ) # => #<File:file.rb>
* 其中的w是表示可以写，还有很多模式：r, r+, w, w+, a, a+,b
B. 打开文件
file = File.open( “sonnet_129.txt” )
file.each { |line| print “#{file.lineno}. ”, line }
file.close
#lineno 是行号
C. 删除或重命名文件
File.new( “books.txt”, “w” )
File.rename( “books.txt”, “chaps.txt” )
File.delete( “chaps.txt” )
3. 操作URI
require 'open-uri'
url = “http://www.google.com/search?q=ruby”
open(url) { |page| page_content = page.read()
links = page_content.scan(/<a class=l.*?href=\"(.*?)\"/).flatten
links.each {|link| puts link}
}
4. File Inquiries
File::open(“file.rb”) if File::exists?( “file.rb” )
File.file?( “sonnet29.txt” ) # => true
# try it with a directory
File::directory?( “/usr/local/bin” ) # => true
＃ 是否是目录
# try it with a file...oops
File::directory?( “file.rb” ) # => false
＃ 文件操作权限
File.readable?( “sonnet_119.txt” ) # => true
File.writable?( “sonnet_119.txt” ) # => true
File.executable?( “sonnet_119.txt” ) # => false
system(“touch chap.txt”) # Create a zero-length file with a system command
File.zero?( “chap.txt” ) # => true
＃ 文件大小
# Get its size in bytes withsize? orsize:
File.size?( “sonnet_129.txt” ) # => 594
File.size( “sonnet_129.txt” ) # => 594
# 文件类型
# Finally, inquire about the type of a file withftype:
File::ftype( “file.rb” ) # => “file”
＃ 创建，修改时间
File::ctime( “file.rb” ) # => Wed Nov 08 10:06:37 -0700 2006
File::mtime( “file.rb” ) # => Wed Nov 08 10:44:44 -0700 2006
File::atime( “file.rb” ) # => Wed Nov 08 10:45:01 -0700 2006
5. Changing File Modes and Owner
file = File.new( “books.txt”, “w” )
file.chmod( 0755 )
or:
file = File.new( “books.txt”, “w” ).chmod(0755 )
system “ls -l books.txt” # => -rwxr-xr-x 1 mikejfz mikejfz 0 Nov 8 22:13
books.txt
